Never was good at desserts. I would think brownies or maybe a grilled fruit like pineapple. My mother has been experimenting with making a smores cookie/mini-cupcake. Pretty much a piece of gram cracker, a Hersey kiss and then a mini marshmallow toasted in the oven.
I love barbecue and often cook it. Since barbecue is not a light meal, after it, you need a light dessert. I usually have ice cream or fruit salad. Perfectly combined, refreshing and after a heavy meal just goes well. It already depends on your traditions, preferences and desires. I noticed that this idea is great after one event that I held. I rented a food truck nyc for my charity event, and served barbecue and ice cream with fruit for dessert, so everyone was delighted and drew attention to my culinary abilities. Thinking about food truck business.